FIELD: organic chemistry, amino acids, chemical technology. SUBSTANCE: invention relates to method for preparing compound (I) with delayed release of an active component that involves compound of the formula (A): 
and polymer comprising lactide, glycolide monomers and monomers of tartaric acid taken in the amount 71-73; 26-28 and 1-3%, respectively being amino- -group of compound (A) is bound by ionic linkage with carboxyl group of polymer acid monomers. Indicated method involves the step of interaction of an aqueous solution (A) with polymer or its salt in mixture of acetonitrile and water where weight ratio of acetonitrile and water is about 3:1, respectively, at temperature about 0-5 C until compound (I) will be formed. Invention relates to method for preparing microparticles of compound (I) by spraying solution of compound (I) in ethyl acetate into isopropyl alcohol to obtain dispersion microparticles of compound (I). EFFECT: improved preparing method. 7 cl, 1 dwg
